So, this is based on a very old story, which apparently predates and influenced the later legend of King Arthur, to some degree, as well as influencing any number of other things. I'm not really familiar with the story, but I gather it's been told in countless different ways over the centuries, so it's probably not a big deal if this movie tells it differently, as well. It might be a bit of a problem that it's wildly historically inaccurate, but whatever. It's just a story, so you might as well suspend your disbelief and just try to enjoy it. I should also say I was a bit torn over what category to put my review in, the main contenders being "action/adventure" and "romantic movies." But ultimately I went with period pieces, partly because it is set in another time (albeit one riddled with historical inaccuracies, as I mentioned), and partly because both the action and romance aspects (as well as the political aspect) were pretty much equally important to me, so... I see this as a sort of compromise.

Anyway, it's set in "the Dark Ages," sometime after the fall of the Roman Empire. For the purposes of this story, Britain is divided among a number of different groups. But the important thing is, again for the purposes of this movie, all of these groups, collectively known as Britons, have been subjugated by the Irish. (Yeah, I know, right?) At the start of the movie, Lord Marke of Cornwall is set to become king of all the Britons, as the various lords have come together to sign a treaty, and together they would be more powerful than the Irish (who are ruled by King Donnchadh). Unfortunately, the Irish have found out about this meeting, and attack. Many Britons are killed, including both the parents of a boy named Tristan, as well as Marke's pregnant wife. Marke himself saves Tristan's life, and loses a hand while doing so. After that, he and his sister take Tristan in and raise him, along with Marke's sister's own son, Melot. (I don't think I ever heard Marke's sister's name, but she's really not that important to the story.) Oh, and btw, Melot's father had been killed by the Irish, too.

The movie flashes forward nine years, and Tristan and Melot are now young men. They're friends, I guess, though it will become clear that Melot bears some degree of resentment toward Tristan, who has become the greatest of Marke's warriors, beloved by the people, as well as more respected by Marke than his own nephew is. (I should say, Melot isn't such a bad guy, and in fact is probably wiser than Tristan, but his understandable resentment will eventually lead him to make an unwise decision. But I'm getting ahead of myself.) Anyway, Donnchadh sends his warriors (led by a general named Morholt) to obtain slaves as tribute from the Britons. This causes Tristan to forge an alliance among the various peoples to free the slaves. In the battle, he kills Morholt, but is apparently mortally wounded, himself. So, his people send him off on a funeral boat, which somehow floats all the way to Ireland, where he is found by the beautiful Princess Isolde and her maid, Bragnae. Isolde decides to hide him and nurse him back to health (we had seen earlier that Morholt's sword was coated with poison, and that Isolde knew the antidote), and of course they fall in love (though she doesn't tell him her real name).

Eventually, he has to return to Britain, but soon after that, Donnchadh offers a treaty which includes giving his daughter Isolde as part of the prize in a tournament to be held, in which the various British lords (or their champions) would compete. (This, of course, was a trick to keep the Britons from uniting under a single king.) Tristan decides to compete as Marke's champion, which would not only end up making Marke king of Britain, but also would mean Marke got to marry Isolde (who of course Tristan didn't know was the woman he had fallen in love with). The only real competition was from Lord Wictred, who fought personally, rather than choosing a champion. However, he apparently colluded with the Irish I guess, and with his own people, who let him win his matches. So by the end, when Wictred went up against Tristan, he was still fairly fresh, whereas Tristan was in pretty bad shape, having won his earlier fights the hard way. But he won anyway.

So all that basically sets up the main problem, romantically speaking, which is that Isolde has to marry Marke, who has no idea that Tristan and Isolde are in love. (Of course, Marke is himself a pretty nice guy, who Tristan loves as both surrogate father and king; and Marke genuinely wants to make Isolde happy.) I don't really want to divulge any more of the plot, but of course there's more politics, battles, and conspiracy between Donnchadh and Wictred, and the secret love between Tristan and Isolde will end up complicating all that the Britons have worked so hard for. It's all very tragic and epic and whatnot. And... it's not a movie I think I ever need to see again, but I did think it was a pretty awesome story, totally worth watching once.